Should have been in the pen but now my pen write with morphine

Lyric Meaning

Instead of being in the “pen” (short for “penitentiary”) for a drug related crime like some of his peers from Compton, Kendrick wrote with his pen, which released rhymes that were as dope as morphine. An overdose of morphine will kill you, which speaks to how deadly Kendrick’s rhymes can be when he’s on.